Is AlCl3 acidic or basic?

[Chem_Mod]

Is AlCl3 acidic or basic since Cl- anion is neutral?

[Chem_Mod]

The Cl- anion is neutral, but the Al3+ is not. From the reaction AlCl3 + 3H2O <=> Al(OH)3 + 3HCl, HCl is a strong acid, so it will dissociate in water to form H+ and Cl-. As a result of this reaction, the solution will be acidic, with a pH < 7.

[Emily_Stenzler_2H]

The Cl- anion is neutral, but the Al3+ is not. From the reaction AlCl3 + 3H2O <=> Al(OH)3 + 3HCl, HCl is a strong acid, so it will dissociate in water to form H+ and Cl-. As a result of this reaction, the solution will be acidic, with a pH < 7.

so does this mean AlCl3 is a weak base since its conjugate acid is strong?

[Anna Li 3B]

The Cl- anion is neutral, but the Al3+ is not. From the reaction AlCl3 + 3H2O <=> Al(OH)3 + 3HCl, HCl is a strong acid, so it will dissociate in water to form H+ and Cl-. As a result of this reaction, the solution will be acidic, with a pH < 7.

so does this mean AlCl3 is a weak base since its conjugate acid is strong?

No, it means AlCl3 is a weak acid, because the only part of the molecule that is contributing to the pH of the solution is the Al+3 ion. The conjugate base of a strong acid has very little impact on the pH of the solution (with the case of Cl- and its conjugate acid, HCl). AlOH3, the conjugate base for Al3+, is a weak base and so Al3+ will be a weak acid.